This invention relates to poured concrete wall forms, and more particularly, to connecting hardware for panels coupled together and used to construct the concrete wall form.
It is well known in the art to use prefabricated reusable panel units to construct a wall form for a poured concrete wall. The hardware associated with such panels connects the panels to one another to form the wall form.
Typically, each panel has a marginal frame projecting rearwardly from a back face of the panel to include a flange along the spaced side edges of the panel. The flanges are adapted to be positioned in an edge to edge relationship with the flange of an adjacent panel to construct a concrete wall form. Holes in the flanges of the adjacent panels can be aligned to receive therethrough the shank of a pin or a bolt. The bolt or pin may pass through the ends of tie-rods and are held in position commonly by wedges which are driven though a slot in the shank of the bolt or pin. As the wedges are driven in place, the abutting flanges of the adjacent panel units are drawn together. The pins and wedges constitute a simple mechanism for effectively coupling the panels together. The pins and wedges can be removed from the panels during the dismantling of the wall form by knocking out the wedges from the slots and sliding the pins from their holes to release the adjacent panel units and the pin from the tie-rod now embedded in the cured concrete.
In the construction of a concrete wall form, a large quantity of hardware is necessary to connect the numerous panels together. Each pair of adjacent panels is typically connected together by multiple, typically three to four, pin and wedge combinations. After the spaced wall forms are constructed and the concrete poured, the panels and pins attaching the panels experience significant hydrodynamic forces resulting from the pouring and curing of the concrete. The large forces experienced by the pins often make it difficult to remove the pins from the flanges of the adjacent panels once the concrete is cured. Commonly, a hammer or other tool is required to dislodge the wedge from the pin and to dislodge the pin from the flanges of the adjacent panels.
One of the primary purposes of the tie rods extending between the spaced wall forms is to maintain the position of the wall forms relative to one another during the pouring and curing of the concrete. As a result, the tie rods exert a significant amount of force on the pins they are attached to in order to hold the panels in place during the concrete pouring and curing. Therefore, the pins are often very difficult to remove from the flanges and to release from the attached tie rods.
Furthermore, the wall forms are commonly constructed in excavated areas such as ditches and trenches when preparing the wall form for a poured concrete wall in a residential basement or below ground floor of a commercial building. As such, the work space for constructing and disassembling the wall form and for the workers to maneuver and manipulate the associated hardware is extremely tight and limited. Therefore, the installation and removal of the pins and wedges is even more difficult and problematic.
Therefore, a need exists in the industry for an attachment mechanism for coupling adjacent panels and constructing a poured concrete wall form which is easily and conveniently installed and most importantly disassembled by the workers in the field. Such an attachment segment must be robust enough to withstand the concrete forces, economical to manufacture and preferably be compatible with existing wall form panels.